Improvement in stamp-heads for crushing ores



i NH@ STATES PATENT Onnrcn.

llllPliOVElVlENl" IN STAMP-HEADS FOR CRUSHING ORES.

Specification forming part of Letters Patent No. 36,302, dated August 26, 1862.

To all whom, it may concern:

Beit known that I, FRANcrs MURRAY, of the city of Baltimore, in the State of Maryland, have invented a new and Improved Stamp- Head for Reducing Ores; `and I do hereby de-V clare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, like letters indicating in the several figures the same or analogous parts, and in which drawings- Figure l is a perspective view of my stamphead; Fig. 2, a longitudinal vertical section; Fig. 3, a perspective view of the shoe or working-face detached from the main portion of the stamphead, and Fig. 4t a cross-section through line w 00 of Fig. 2. Fig. 5 is a sectional view of a working size of my stamp-head, and shows a solid piece of ductile metal, as at F, of the required thickness for the stamp-head when of the size indicated. Figs. 6, 7, and 8 are reduced views of the stamp-head represented at Fig. 5, and are intended to illustrate Vthe effect upon the duct-ile metal F of the repeated blows of the stamphead upon the ore.

Stamp -h'eads for reducing ores have in some instances heretofore been constructed with the entire head in one continuous piece or mass of cast metal, in which case the workingfacehas usually been chilled to resist the wearing action of the ore; but this mode of construction is objectionable, since the entire mass must be recast whenever the working-face becomes worn out; or they have been cast entire and faced with steel, or made of a cluster of steel bars and held in place by bands, either of which cases imposes a heavy expense of construction; or they have been made with an upper section of cast-iron flowed around steel or wroughtiron v'bars placed vertically to the working-face ofthe stamp-head, in which case the bars are liable to work loose and the surrounding cast-iron to sh'elloff, and, aside from these objections, the constant and powerful jar to which that portion of the stamp-head is subject which does not come in immediate contact with the ore, when it is made principally of cast-iron, causes the granulation of the metal, and so weakens its tenacity that after a little use the upper portion becomes fractured and useless; or, the entire stamp-head has been made of cast chilled metal-a process somewhat difficult to successfully perform, owing to aliability of fracture in the act of chilling7 so large a mass of metal as is required to make a stamp-head of the proper size and weight, and which, when its working-face becomes worn through to the wrought-iron core that produces the internal chill, renders the whole remaining mass of chilled iron useless.

The nature of my invention consists in so constructing iron shoes for the lower end of stamp-heads for reducing ores that when said shoes are cast in a chill with a malleable-iron shank, said shank, while it subserves the purpose of chilling the inner portion of the shoe in the process of casting, shall also, after the shoe is cast, serve the purpose of a coupling to secure the shoe to the main portion of the stamp-head.

It also consists in theinterpostion between the shoe and the main portion of the stamphead of a ductile metallic plate or buffer, the reduction of which plate in thickness by the repeated blows of the stamp-head upon the ore shall act not only to relieve the shoe and upper portion of lthe stamp-head from excessive shock, but at the same time that it yields slightly in thickness shall impart a sufficiently unyielding force to effectively crush the ore.

To enable others skilled in the arts to make and use my invention, I will proceed to describe its construction and operation.

I construct my stamp head in two separate parts--to wit,an upper or maj or portion, A, and alower or minor portion,B-the lower portion, B, being cast in a chill with a wrought-iron shank, C, dovetailed at its lower end, as in Fig. 2, and slotted near the top to receive an iron key,l D, which passes through it and the upper portion of the stamp-head, thus forming a perfect chill throughout the minor portion B by means of the wrought-iron shank in the center and the outer mold or chill in which it is cast.

The upper or major portion, A, of the stamphead is cast with a center opening to receive an iron or wooden shank, E, and slotted like the lower portion to receive a key, D', for the purpose of securing it to the shank E. On the upper face of the shoe B, as at f, Fig. 3, and F, Fig. 5, and surrounding the shank O, I place a plate of copper or other proper ductile metal. This metallic sheet or plate f acts as a bader to receive the blow of the face of the shoe upon the ore, and relieves the shoe B from the excessive shock of such blow. AIt' which time it needs renewal, the special objectA ofmy invention so far as it relates to this be` 4ing to utilize a buffer which, while it saves the stamp-head from destructive percussive effects, as described, by its gradually diminishing in thickness, shall yet possess such density as will at' the same time impart a proper degree of crushing force to reduce the ore.`

By my method of constructing a stamp-head it will be seen that the working portion or shoe B can be renewed when worn out by merely removing it from the major portion A and recasting the metal around the shank C; that by such renewal, the cost of which is triiiing, all expensive resort to steel facing and steel bars is avoided, and that by utilizing a buier, as described, the shoe B, as well as the main portion A of the stamp'head, is in a great measure'preserved from injury arising from powerful blows and jars, and, iinally, that Whenever the buf'erf becomes so reduced in thickness as to require renewal the shoe B may readily be removed by knocking out the key D andanew'or an additional buffer interposed between the upper and lower sections of the v stamp-head. i i i Having thus described my said invention, what I claimas new, and desire to secure by Letters Patent ofthe United States, is

1. In astamp-head the working-face of which iscast in a chill and is capable at pleasure of being attached to or removed from an upper or main section, so constructing the same by casting it around and upon awroughtiron shank that said shank shall serve as a coupling to unite the shoe to the upper section of the stamphead, and also be capable of being used thereafter to cast a new working face or shoe upon, substantially as described.

2. In connection with astamp-head for crushing ores, the use of aductile metallic buffer or its equivalent, substantially in the manner and wfor the purpose'described.

FRAN GIS MURRAY.

In presence of w i ROBERT GILMORE, JAMES MONTGOMERY, W. H. HAYWARD. 

